Field
Aspects of the present invention generally relate to an image forming apparatus that forms an image on a recording material and detection of a deterioration state of a conveying unit that conveys the recording material.
Description of the Related Art
In an image forming apparatus, a deterioration state (also referred to as “life”) of a conveying unit, such as a conveying roller, that conveys a recording material on which an image is formed is generally determined based on the total number of sheets of the recording material conveyed by the conveying unit, the total driving time of the conveying unit, changes in speed at which the recording material is conveyed, or the like. A threshold used in the determination of the life of the conveying unit is set such that the performance of the conveying unit in conveying the recording material does not affect the quality and functions (for example, image quality, conveying performance, and the like) of the image forming apparatus. For example, in Japanese Patent Laid-Open No. 4-277780, a technique is proposed in which the speed at which the recording material is conveyed by a fixing unit, which is an example of the unit that conveys a recording material, is detected, and the life of the fixing unit is determined based on the amount of change from an initial value (initial conveying speed) before deterioration of the fixing unit due to repeated use.
The performance of the conveying unit in conveying the recording material, however, changes depending on other factors such as an environment (temperature, humidity, and the like) in which the image forming apparatus is installed, as well as the deterioration due to repeated use.